diff --git a/src/libCom/osi/os/cygwin32/systemCallIntMech.cpp b/src/libCom/osi/os/cygwin32/systemCallIntMech.cpp
deleted file mode 100644
index c31bcef2d..000000000
--- a/src/libCom/osi/os/cygwin32/systemCallIntMech.cpp
+++ /dev/null
@@ -1,23 +0,0 @@
-
-/*************************************************************************\
-* Copyright (c) 2002 The University of Chicago, as Operator of Argonne
-*     National Laboratory.
-* Copyright (c) 2002 The Regents of the University of California, as
-*     Operator of Los Alamos National Laboratory.
-* EPICS BASE Versions 3.13.7
-* and higher are distributed subject to a Software License Agreement found
-* in file LICENSE that is included with this distribution. 
-\*************************************************************************/
-/* $Id$ */
-/*
- *      Author:		Jeff Hill 
- */
-
-#define epicsExportSharedSymbols
-#include "osiSock.h"
-
-enum epicsSocketSystemCallInterruptMechanismQueryInfo 
-        epicsSocketSystemCallInterruptMechanismQuery ()
-{
-    return esscimqi_socketCloseRequired;
-}
diff --git a/src/libCom/osi/os/posix/systemCallIntMech.cpp b/src/libCom/osi/os/posix/systemCallIntMech.cpp
index 2cd37b1aa..5b755139e 100644
--- a/src/libCom/osi/os/posix/systemCallIntMech.cpp
+++ b/src/libCom/osi/os/posix/systemCallIntMech.cpp
@@ -13,6 +13,7 @@
  *      Author:		Jeff Hill 
  */
 
+#define epicsExportSharedSymbols
 #include "osiSock.h"
 
 enum epicsSocketSystemCallInterruptMechanismQueryInfo